Deflecting devices in which sheet material is deflected by 90° or 180° are for example used in bank note processing apparatus. However, conventional deflecting devices are either not suitable for deflecting a continuous flow of bank notes in such a fashion at a high throughput speed, or at least require a comparatively large space and/or have a comparatively elaborate structure.
From US-2005/0029168 A1 for example a bank note processing apparatus consisting of several modules is known, in which the deflecting device according to the invention described below can also be used advantageously. This bank note processing apparatus is configured as a desktop device and serves to single the bank notes of a stack of bank notes placed in an input pocket by an operator, to check the singled bank notes in regard of characteristic features by means of suitable measuring and analysis devices, to sort the checked bank notes in accordance with the respective check result, and to stack them in accordance with the sorting result in a predetermined output pocket by means of a spiral slot stacker. The output pockets are arranged partly side by side and partly on top of each other in such a fashion that all output pockets are accessible to the operator as easily as possible. Within the modules the bank notes are generally transported in transverse orientation.
It is a disadvantage of this bank note processing apparatus that a very voluminous transport path, formed by guide plates and twisted conveyor belts, is provided to turn the bank notes in such a fashion that they can be further transported sideways to the adjacent modules in transverse orientation. Therein the bank notes are first turned around their transport axis by 90° by means of the twisted conveyor belts, subsequently the bank notes are deflected by 90° around an axis oriented transversely to the transport path, and transferred to the adjacent module in this orientation. There the bank notes are returned to their original orientation by firstly deflecting them by 90° again and subsequently again turning them by 90° around the transport axis by means of the twisted conveyor belts. This method for transferring the bank notes from one module to an adjacent module while maintaining the orientation of the sheet material relative to the transport direction is very elaborate in regard of space requirement and structural configuration, however at least it allows deflecting a continuous flow of bank notes at a high throughput speed.
From WO97/33823 an apparatus for changing the transport direction of single sheets is known, which could probably be used in the bank note processing apparatus known from US-2005/0029168 A1 to deflect the bank notes by 90° to the adjacent modules. Bank notes transported in transverse orientation would then, after deflection by 90°, be passed on to the adjacent module in longitudinal orientation, and there could again be deflected by 90° in a corresponding fashion, thereby enabling their further processing in transverse orientation. However, this apparatus has the disadvantage that the deflecting area has to be cleared first before the subsequent bank note can enter the deflecting area. With this apparatus it is therefore impossible to deflect a continuous flow of bank notes at a high throughput speed.
DE 196 32 224 A1 also describes an apparatus for deflecting sheet material. There it is proposed to do without deflecting rollers in the deflecting area and to extend conveyor belts of the supplying and the removing transport paths respectively beyond the deflecting area in such a fashion that the bank note is removed from the deflecting area by means of the conveyor belt of the removing transport path. By means of a lifting-roller system the conveyor belt of the removing transport path is pressed against the removal plane of the deflecting area every time a bank note has been supplied to the removal plane. In order to increase the throughput while avoiding the danger of collision of successive bank notes described above, a special embodiment provides to use a switch for supplying the successive bank notes alternately to a first or a second removal plane, so that the subsequent sheet can already be supplied to the second removal plane before the preceding sheet has been removed entirely from the first removal plane and passed on. Correspondingly two removal systems are required, one for each removal plane. It is true that in this fashion a continuous flow of bank notes can be deflected at a high throughput speed. However, providing several removal systems requires a high constructive effort.